A thick sphere of icy debris known as the Oort cloud shrouds the solar system. Other star systems may harbor similar icy reservoirs, and those clouds may be visible in the universe’s oldest light, researchers report.

Astronomer Eric Baxter of the University of Pennsylvania and colleagues looked for evidence of such exo-Oort clouds in maps of the cosmic microwave background, the cool...

First, a pair of cosmic protons smash together at unimaginable speeds. The tremendous energy of their crash would create a tiny, ephemeral black hole, so small that it would last just a fraction of a second before evaporating.

Where the black hole just was, a bubble of space with entirely different laws of physics than the universe we inhabit...

There’s more to a galaxy than meets the eye. Galaxies’ bright stars seem to spiral serenely against the dark backdrop of space. But a more careful look reveals a whole lot of mayhem.

“Galaxies are just like you and me,” Jessica Werk, an astronomer at the University of Washington in Seattle, said in January at a meeting of the American Astronomical Society. “They live their lives in a...

When Voyager 1 revealed lightning on Jupiter in 1979, something about the flashes didn’t make sense. From a distance, it seemed like the radio waves from the massive planet’s lightning bolts didn’t reach the high frequency emitted by lightning on Earth.

But the Juno spacecraft, which has been orbiting much closer to Jupiter’s surface for the last two years, has helped solve the mystery...

A measly 250 million years after the Big Bang, in a galaxy far, far away, what may be some of the first stars in the universe began to twinkle. If today’s 13.8-billion-year-old universe is in middle age, it would have been just starting to crawl when these stars were born.

Researchers used instruments at the Atacama Large Millimeter/submillimeter Array observatory in Chile to observe...

A DIY universe mimics the physics of the infant cosmos, a team of physicists reports. The researchers hope to use their homemade cosmic analog to help explain the first instants of the universe’s 13.8-billion-year life.

For their stand-in, the scientists created a Bose-Einstein condensate — a state of matter in which atoms are chilled until they all take on the same quantum state. Shaped...

Scientists playing peekaboo with dark matter have entered a new stage of the game.

For the first time, physicists are snooping on some of the likeliest hiding places for hypothetical subatomic particles called axions, which could make up dark matter. So far, no traces of the particles have been found, scientists with the Axion Dark Matter Experiment, ADMX, report April 9 in Physical...

Dark matter is still the shyest particle in physics. New observations show that dark matter in galaxy cluster Abell 3827 stubbornly ignores all other kinds of matter — including itself, astronomers reported April 6 at the European Week of Astronomy and Space Science in Liverpool, England.

The research, also posted online at arXiv.org, negates an earlier finding that stars were separated...

Dust may seem insignificant, but in science, it can cost you a Nobel Prize.

That’s what happened to Brian Keating, a major contributor to the BICEP2 team that claimed in 2014 to have found the first definitive evidence of cosmic inflation (SN: 4/5/14, p. 6), a period of extremely rapid expansion just after the...